/*
Copyright (C) 1996-1997 Id Software, Inc.

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 3
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
// sv_user.c -- server code for moving users

#include "quakedef.h"

edict_t	*sv_player;

// world
BOOL	onground;


/*
===============
SV_SetIdealPitch
===============
*/
#define	MAX_FORWARD	6

void SV_SetIdealPitch (void)
{
	float	angleval, sinval, cosval;
	trace_t	tr;
	vec3_t	top, bottom;
	float	z[MAX_FORWARD];
	int		i, j;
	int		step, dir, steps;

	if (!((int) sv_player->v.flags & FL_ONGROUND))
		return;

	angleval = sv_player->v.angles[YAW] * M_PI * 2 / 360;
	sinval = sin (angleval);
	cosval = cos (angleval);

	for (i = 0; i < MAX_FORWARD; i++)
	{
		top[0] = sv_player->v.origin[0] + cosval * (i + 3) * 12;
		top[1] = sv_player->v.origin[1] + sinval * (i + 3) * 12;
		top[2] = sv_player->v.origin[2] + sv_player->v.view_ofs[2];

		bottom[0] = top[0];
		bottom[1] = top[1];
		bottom[2] = top[2] - 160;

		SV_Move (&tr, top, vec3_origin, vec3_origin, bottom, 1, sv_player);

		if (tr.allsolid)
			return;	// looking at a wall, leave ideal the way is was

		if (tr.fraction == 1)
			return;	// near a dropoff

		z[i] = top[2] + tr.fraction * (bottom[2] - top[2]);
	}

	dir = 0;
	steps = 0;

	for (j = 1; j < i; j++)
	{
		step = z[j] - z[j - 1];

		if (step > -ON_EPSILON && step < ON_EPSILON)
			continue;

		if (dir && (step - dir > ON_EPSILON || step - dir < -ON_EPSILON))
			return;		// mixed changes

		steps++;
		dir = step;
	}

	if (!dir)
	{
		sv_player->v.idealpitch = 0;
		return;
	}

	if (steps < 2)
		return;

	sv_player->v.idealpitch = -dir * sv_idealpitchscale->value;
}


/*
==================
SV_UserFriction

==================
*/
void SV_UserFriction (double frametime, float *origin, float *angles, float *velocity)
{
	float	speed, newspeed, control;
	vec3_t	start, stop;
	float	friction;
	trace_t	trace;

	speed = sqrt (velocity[0] * velocity[0] + velocity[1] * velocity[1]);

	if (!speed)
		return;

	// if the leading edge is over a dropoff, increase friction
	start[0] = stop[0] = origin[0] + velocity[0] / speed * 16;
	start[1] = stop[1] = origin[1] + velocity[1] / speed * 16;
	start[2] = origin[2] + sv_player->v.mins[2];
	stop[2] = start[2] - 34;

	SV_Move (&trace, start, vec3_origin, vec3_origin, stop, TRUE, sv_player);

	if (trace.fraction == 1.0)
		friction = sv_friction->value * sv_edgefriction->value;
	else
		friction = sv_friction->value;

	// apply friction
	control = speed < sv_stopspeed->value ? sv_stopspeed->value : speed;
	newspeed = speed - frametime * control * friction;

	if (newspeed < 0)
		newspeed = 0;

	newspeed /= speed;

	velocity[0] = velocity[0] * newspeed;
	velocity[1] = velocity[1] * newspeed;
	velocity[2] = velocity[2] * newspeed;
}

/*
==============
SV_Accelerate
==============
*/

void SV_Accelerate (double frametime, float *origin, float *angles, float *velocity, float wishspeed, float *wishdir)
{
	int			i;
	float		addspeed, accelspeed, currentspeed;

	currentspeed = Vector3Dot (velocity, wishdir);
	addspeed = wishspeed - currentspeed;

	if (addspeed <= 0)
		return;

	accelspeed = sv_accelerate->value * frametime * wishspeed;

	if (accelspeed > addspeed)
		accelspeed = addspeed;

	for (i = 0; i < 3; i++)
		velocity[i] += accelspeed * wishdir[i];
}


void SV_AirAccelerate (double frametime, float *origin, float *angles, float *velocity, float *wishveloc, float wishspeed, float *wishdir)
{
	int			i;
	float		addspeed, wishspd, accelspeed, currentspeed;

	wishspd = VectorNormalize (wishveloc);

	if (wishspd > 30)
		wishspd = 30;

	currentspeed = Vector3Dot (velocity, wishveloc);
	addspeed = wishspd - currentspeed;

	if (addspeed <= 0)
		return;

	//	accelspeed = sv_accelerate->value * frametime;
	accelspeed = sv_accelerate->value * wishspeed * frametime;

	if (accelspeed > addspeed)
		accelspeed = addspeed;

	for (i = 0; i < 3; i++)
		velocity[i] += accelspeed * wishveloc[i];
}


void DropPunchAngle (double frametime)
{
	float	len;

	len = VectorNormalize (sv_player->v.punchangle);

	len -= 10 * frametime;

	if (len < 0)
		len = 0;

	VectorScale (sv_player->v.punchangle, len, sv_player->v.punchangle);
}

/*
===================
SV_NoclipMove

===================
*/
void SV_NoclipMove (double frametime, usercmd_t *cmd, float *origin, float *angles, float *velocity)
{
	vec3_t	forward, right, up;

	AngleVectors (sv_player->v.v_angle, forward, right, up);

	velocity[0] = forward[0] * cmd->forwardmove + right[0] * cmd->sidemove;
	velocity[1] = forward[1] * cmd->forwardmove + right[1] * cmd->sidemove;
	velocity[2] = forward[2] * cmd->forwardmove + right[2] * cmd->sidemove;
	velocity[2] += cmd->upmove * 2; // doubled to match running speed

	if (Vector3Length (velocity) > sv_maxspeed->value)
	{
		VectorNormalize (velocity);
		VectorScale (velocity, sv_maxspeed->value, velocity);
	}
}

/*
===================
SV_WaterMove

===================
*/
void SV_WaterMove (double frametime, usercmd_t *cmd, float *origin, float *angles, float *velocity)
{
	int		i;
	vec3_t	wishvel;
	float	speed, newspeed, wishspd, addspeed, accelspeed;
	vec3_t	forward, right, up;

	// user intentions
	AngleVectors (sv_player->v.v_angle, forward, right, up);

	for (i = 0; i < 3; i++)
		wishvel[i] = forward[i] * cmd->forwardmove + right[i] * cmd->sidemove;

	if (!cmd->forwardmove && !cmd->sidemove && !cmd->upmove)
		wishvel[2] -= 60;		// drift towards bottom
	else
		wishvel[2] += cmd->upmove;

	wishspd = Vector3Length (wishvel);

	if (wishspd > sv_maxspeed->value)
	{
		VectorScale (wishvel, sv_maxspeed->value / wishspd, wishvel);
		wishspd = sv_maxspeed->value;
	}

	wishspd *= 0.7f;

	// water friction
	speed = Vector3Length (velocity);

	if (speed)
	{
		newspeed = speed - frametime * speed * sv_friction->value;

		if (newspeed < 0)
			newspeed = 0;

		VectorScale (velocity, newspeed / speed, velocity);
	}
	else
		newspeed = 0;

	// water acceleration
	if (!wishspd)
		return;

	addspeed = wishspd - newspeed;

	if (addspeed <= 0)
		return;

	VectorNormalize (wishvel);
	accelspeed = sv_accelerate->value * wishspd * frametime;

	if (accelspeed > addspeed)
		accelspeed = addspeed;

	for (i = 0; i < 3; i++)
		velocity[i] += accelspeed * wishvel[i];
}

void SV_WaterJump (float *origin, float *angles, float *velocity)
{
	if (sv.time > sv_player->v.teleport_time || !sv_player->v.waterlevel)
	{
		sv_player->v.flags = (int) sv_player->v.flags & ~FL_WATERJUMP;
		sv_player->v.teleport_time = 0;
	}

	velocity[0] = sv_player->v.movedir[0];
	velocity[1] = sv_player->v.movedir[1];
}


/*
===================
SV_AirMove

===================
*/
void SV_AirMove (double frametime, usercmd_t *cmd, float *origin, float *angles, float *velocity)
{
	int		i;
	vec3_t	wishvel, wishdir;
	float	fmove, smove;
	float	wishspeed;
	vec3_t	forward, right, up;

	AngleVectors (angles, forward, right, up);

	fmove = cmd->forwardmove;
	smove = cmd->sidemove;

	// hack to not let you back into teleporter
	if (sv.time < sv_player->v.teleport_time && fmove < 0)
		fmove = 0;

	for (i = 0; i < 3; i++)
		wishvel[i] = forward[i] * fmove + right[i] * smove;

	if ((int) sv_player->v.movetype != MOVETYPE_WALK)
		wishvel[2] = cmd->upmove;
	else
		wishvel[2] = 0;

	Vector3Copy (wishdir, wishvel);
	wishspeed = VectorNormalize (wishdir);

	if (wishspeed > sv_maxspeed->value)
	{
		VectorScale (wishvel, sv_maxspeed->value / wishspeed, wishvel);
		wishspeed = sv_maxspeed->value;
	}

	if (sv_player->v.movetype == MOVETYPE_NOCLIP)
	{
		// noclip
		Vector3Copy (velocity, wishvel);
	}
	else if (onground)
	{
		SV_UserFriction (frametime, origin, angles, velocity);
		SV_Accelerate (frametime, origin, angles, velocity, wishspeed, wishdir);
	}
	else
	{
		// not on ground, so little effect on velocity
		SV_AirAccelerate (frametime, origin, angles, velocity, wishvel, wishspeed, wishdir);
	}
}

/*
===================
SV_ClientThink

the move fields specify an intended velocity in pix/sec
the angle fields specify an exact angular motion in degrees
===================
*/
void SV_ClientThink (double frametime)
{
	vec3_t v_angle;

	// copy these off so that we don't need to dereference sv_player->v. everywhere
	float *origin = sv_player->v.origin;
	float *angles = sv_player->v.angles;
	float *velocity = sv_player->v.velocity;

	if (sv_player->v.movetype == MOVETYPE_NONE)
		return;

	onground = (int) sv_player->v.flags & FL_ONGROUND;

	DropPunchAngle (frametime);

	// if dead, behave differently
	if (sv_player->v.health <= 0)
		return;

	// angles
	// show 1/3 the pitch angle and all the roll angle
	Vector3Add (v_angle, sv_player->v.v_angle, sv_player->v.punchangle);
	angles[ROLL] = V_CalcRoll (angles, velocity) * 4;

	if (!sv_player->v.fixangle)
	{
		angles[PITCH] = -v_angle[PITCH] / 3;
		angles[YAW] = v_angle[YAW];
	}

	if ((int) sv_player->v.flags & FL_WATERJUMP)
	{
		SV_WaterJump (origin, angles, velocity);
		return;
	}

	if (sv_player->v.movetype == MOVETYPE_NOCLIP)
		SV_NoclipMove (frametime, &host_client->cmd, origin, angles, velocity);
	else if (sv_player->v.waterlevel >= 2)
		SV_WaterMove (frametime, &host_client->cmd, origin, angles, velocity);
	else SV_AirMove (frametime, &host_client->cmd, origin, angles, velocity);
}


/*
===================
SV_ReadClientMove
===================
*/
void SV_ReadClientMove (usercmd_t *move)
{
	int		i;
	vec3_t	angle;
	int		bits;

	// read ping time
	host_client->ping_times[host_client->num_pings % NUM_PING_TIMES] = sv.time - MSG_ReadFloat ();
	host_client->num_pings++;

	// read current angles
	for (i = 0; i < 3; i++)
	{
		if (sv.protocol == PROTOCOL_NETQUAKE)
			angle[i] = MSG_ReadAngle ();
		else angle[i] = MSG_ReadAngle16 ();
	}

	VectorCopy (angle, host_client->edict->v.v_angle);

	// read movement
	move->forwardmove = MSG_ReadShort ();
	move->sidemove = MSG_ReadShort ();
	move->upmove = MSG_ReadShort ();

	// read buttons
	bits = MSG_ReadByte ();
	host_client->edict->v.button0 = bits & 1;
	host_client->edict->v.button2 = (bits & 2) >> 1;

	i = MSG_ReadByte ();

	if (i)
		host_client->edict->v.impulse = i;
}


/*
===================
SV_ReadClientMessage

Returns FALSE if the client should be killed
===================
*/
BOOL SV_ReadClientMessage (void)
{
	int		ret;
	int		cmd;
	char	*s;

	do
	{
nextmsg:;
		ret = NET_GetMessage (host_client->netconnection);

		if (ret == -1)
		{
			return FALSE;
		}

		if (!ret)
			return TRUE;

		MSG_BeginReading ();

		while (1)
		{
			if (!host_client->active)
				return FALSE;	// a command caused an error

			if (msg_badread)
			{
				return FALSE;
			}

			cmd = MSG_ReadChar ();

			switch (cmd)
			{
			case -1:
				goto nextmsg;		// end of message

			default:
				return FALSE;

			case clc_nop:
				break;

			case clc_stringcmd:
				s = MSG_ReadString ();

				if (host_client->privileged)
					ret = 2;
				else ret = 0;

				if (Q_strncasecmp (s, "status", 6) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "god", 3) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "notarget", 8) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "fly", 3) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "name", 4) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "noclip", 6) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "say", 3) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "say_team", 8) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "tell", 4) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "color", 5) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "kill", 4) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "pause", 5) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "spawn", 5) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "begin", 5) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "prespawn", 8) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "kick", 4) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "ping", 4) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "give", 4) == 0)
					ret = 1;
				else if (Q_strncasecmp (s, "ban", 3) == 0)
					ret = 1;

				if (ret == 2)
					Cbuf_InsertText (s);
				else if (ret == 1)
					Cmd_ExecuteString (s, src_client);
				else
					Con_Printf (PRINT_DEVELOPER, "%s tried to %s\n", host_client->name, s);

				break;

			case clc_disconnect:
				return FALSE;

			case clc_move:
				SV_ReadClientMove (&host_client->cmd);
				break;
			}
		}
	} while (ret == 1);

	return TRUE;
}


/*
==================
SV_RunClients
==================
*/
void SV_RunClients (double frametime)
{
	int	i;

	for (i = 0, host_client = svs.clients; i < svs.maxclients; i++, host_client++)
	{
		if (!host_client->active)
			continue;

		sv_player = host_client->edict;

		if (!SV_ReadClientMessage ())
		{
			SV_DropClient (FALSE);	// client misbehaved...
			continue;
		}

		if (!host_client->spawned)
		{
			// clear client movement until a new packet is received
			memset (&host_client->cmd, 0, sizeof (host_client->cmd));
			continue;
		}

		// always pause in single player if in console or menus
		if (!sv.paused && (svs.maxclients > 1 || key_dest == key_game))
			SV_ClientThink (frametime);
	}
}

